Technical Field
Embodiments of the present disclosure generally relate to a three-dimensional semiconductor device and more particularly to a three dimensional semiconductor device having improved structural stability.
Discussion of Related Arts
A nonvolatile memory device may keep stored-data even at a power-off state. As a two-dimensional memory device including a single array of memory cells on a silicon substrate reaches its integration limit, a three-dimensional (3D) non-volatile memory device including a stack of memory cells on a silicon substrate has been suggested.
For stacking the memory cells, the 3D non-volatile memory device may have vertical alternating layers of conductive and insulating materials. Further, for process efficiency, during various phases of the fabrication process, sacrificial insulating layers may also be vertically arranged temporarily as may be needed only to be replaced later with conductive layers. Replacement of the sacrificial layers with conductive layers is generally a challenging process and may inadvertently lead to a partial warp of collapse of the stack. As a result, a bridge may occur between one or more conductive layers, and thus the yield of the semiconductor device may be reduced.